Thermal monitoring circuit frequently is implemented in electronic devices to avoid device damage due to overheating. Conventional implementations typically are based on the assumption that many devices in the monitoring circuit will be matched and will operate at the same temperature, an assumption that often is not valid and therefore results in poor precision in the detection of the desired temperature threshold. This precision error typically increases as the temperature gradient increases, thereby increasing the risk that an over-temperature event will go undetected and thereby damage a component, or that an otherwise acceptable temperature will be erroneously interpreted as an over-temperature event, which typically would result in an unnecessary shut-down or performance degradation of one or more co-located circuit components.
Further, some conventional implementations use a single thermal detection device to monitor temperature, which often reduces matching problems, but these conventional implementations often use a band-gap reference or other separate voltage reference in order to compare and generate a voltage transition at a threshold temperature. Further, in the event that a number of locations are to be monitored, the same monitoring circuit is repeated for each location in addition to the thermal detection device at each location, resulting in excessive area utilization and hence increased cost. Accordingly, an improved technique for temperature monitoring for an electronic device would be advantageous.
The use of the same reference symbols in different drawings indicates similar or identical items.